This invention relates to a drafting instrument and more particularly to a drafting instrument including a pair of generally triangular shaped drafting plates coupled to opposite sides of a central mounting member for swinging movement between any one of a plurality of different, spaced apart positions so that a straight edge is presented in any one of a plurality of different positions.
Drafting instruments have been provided heretofore which include a relatively adjustable triangularly shaped section. Drafting instruments of the type described herein are conventionally utilized by a draftsman in connection with a drafting table including a parallel bar or T-square which extends parallel to the upper and lower edges of an upwardly inclined drafting table. The T-square or parallel bar has upper and lower parallel edges against which a drafting instrument can be placed. A draftsman will preferably place the drafting instrument against the upper edge of the T-square or parallel bar. With conventional drafting instruments, it is sometimes necessary that the draftsman work from the lower edge of the T-square or parallel bar. The placement of the drafting instrument against the lower edge of the parallel bar is awkward and time consuming.
Draftsman frequently refer to angles between 0.degree. and 90.degree., 90.degree. to 180.degree., 180.degree. to 270.degree., and 270.degree. to 360.degree., as being in the first, second, third, and fourth quadrants, respectively.
As an aid to uniform lettering, a draftsman will frequently place a lettering set against the drafting instrument which in turn is placed against the parallel bar. The prior art drafting instruments are particularly limited when inverted lettering, as viewed from the bottom of the drafting paper, is to be accomplished at obtuse angles in the second quadrant.
Accordingly, it is an object of the present invention to provide a new and novel drafting instrument.
Another object of the present invention is to provide a new and novel drafting instrument which will permit greater flexibility to a draftsman drawing lines at various angles.
A further object of the present invention is to provide a new and novel time saving drafting instrument.
A still further object of the present invention is to provide a new and novel drafting instrument which can be adjusted to any one of a plurality of positions in any quadrant.
Another object of the present invention is to provide a new and novel drafting instrument which can be mounted against the upper edge of a drafting table parallel bar and provides a straight edge in the second quadrant in confronting relation to the upper edge of the parallel bar.
Another object of the present invention is to provide a drafting instrument which, when mounted on the upper edge of a drafting table parallel bar, will present a lettering edge in the second quadrant against which a lettering set may be mounted so that inverted letters may be printed in the second quadrant on the drafting paper.
Yet another object of the present invention is to provide a new and novel drafting instrument including a pair of generally triangularly shaped members coupled to a central mounting member for swinging movement between any one of a plurality of different positions.
Still another object of the present invention is to provide a new and novel drafting instrument including a pair of similarly constructed, generally triangularly shaped templates mounted on laterally opposite sides of a central member for movement between any one of a plurality of different spaced apart positions in which corresponding edges are disposed in parallel relation at any one of a plurality of differing spaced apart locations.
Another object of the present invention is to provide a new and novel drafting instrument including a pair of similarly constructed drafting templates each including a triangularly shaped section and a truncated triangle section, and a central planar coupling member mounting the templates on laterally opposite sides thereof for swinging movement between any selected one of a plurality of different positions.
A further object of the present invention is to provide a new and novel drafting instrument including a pair of identical, generally triangularly shaped drafting plates, each including first and second right angularly related edges, and mechanism mounting the plates for relative swinging movement between positions in which the second edge of one of the members is movable between a position in which the included angle between the first edge of one of said members and the second edge of the other of said members is variable between acute and obtuse angles.
A still further object of the present invention is to provide a new and novel drafting instrument of the type described including protractor mechanism for measuring the angular relationship between the straight edge portions of the pivotally connected drafting plates.
Another object of the present invention is to provide a drafting instrument including a central mounting member having generally parallel end edges and a pair of generally triangularly shaped drafting plates each including a truncated triangle section, and mechanism mounting the drafting plates for movement relative to the central mounting member between positions in which the truncated edges of the triangularly shaped sections lie in the planes of the end edges of the central mounting means and angularly related positions.
These and other objects of the present invention will become more readily apparent as the description thereof proceeds.